Problems from overfilling engine oil.

"Find out what overfilling engine oil does & how to fix it."

We are going to discuss the issue of overfilling the engine oil in your vehicle. And more importantly the solutions to this problem.

What are some of the issues that might arise when there is an excessive amount of oil in the engine? How exactly do you drain that oil? More importantly, how exactly do you determine how much oil is now present in your vehicle's engine?

So let's start with the most reasonable thing: how to check the amount of oil in your engine's reservoir.

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Checking your Oil Levels

Ensure that your vehicle is parked on a surface that is level and flat.

If your vehicle is parked on an incline, you can't get an accurate level of the oil because it is on one side of the sump.

The sump is the large bowl that is located at the bottom of the engine and is where the oil collects.

Find the dipstick

As far as engines are concerned, they all have a dipstick. (99% of them do and I'm sure someone will point out in the comments the exception).

When you look in the front of the engine, and it's often yellow or orange or another bright colour, and you just pull it out.

It's a little stick within a tube that goes into the sump of the engine and the oil will leave a mark on it.

You just pull it out steadily.

Now when you pull that out for the first time, you'll notice that it's covered in oil, and it doesn't make a lot of sense.

Wipe it down, reinsert and repeat

It's Now that you've cleaned it up, repeat the process, but make sure it is fully inserted before you pull it out.

You locate your dipstick, remove it, wipe it clean, replace it, and then slowly remove it from its slot; this will indicate where the liquid level is.

Also check the engine is cold because when the engine is running or has been, all of the oil is around the inside of the engine and you're not going to get the level that is in the engine; instead you'll get the level that is in the bottom of the sump, which is usually much lower.

This is probably where most people go wrong when they fill their oil up; they use the dipstick to determine how much oil they've got in their engine.

You have a mark for empty and you have a mark for maximum, and you should seek to make sure the oil is somewhere between the two, and ideally around the maximum level. Since most automobiles will consume some oil and burn some oil, and you want to make sure you are well inside the threshold.

If you are planning on taking a long trip in the near future, you should check the amount of oil in your vehicle and make sure that there is enough.

What happens with too much oil?

If you are a little over, don't worry, in most engines you can get away with a little above the line, and I've even known manufacturers to overfill the oil slightly.

So, what happens if you overfill your engine oil or if you have an excessive amount of oil in your engine? The crankshaft, which is located at the base of the engine, rotates at speeds of up to six or seven thousand revolutions per minute (rpm).

If you put your hand into some water and slam it about, you'll find that the water isn't as soft as it once was and you feel resistance.

If you strike anything really hard, your hand may become bruised or even injured, and water or engine oil is actually no exception here.

This is especially true if you hit it repeatedly.

Imagine for a moment that your crank is plunging into this reservoir of oil at a very high speed.

It is not going to help the situation in any way the vibrations and splashing are the key issues with this.

Because of this, you do not want your crank splattering in the oil.

Because of the additional work that has to be done, the engine will lose some of its power as a result of this pool of oil that it needs to push through.

The second thing to keep in mind is that continuous agitation of oil will cause the oil to become foamy.

You are essentially creating a froth similar to that of a cappuccino inside of your engine, and this is going to limit the ability of the oil pump to circulate it, and restricts the lubrication in the engine.

Oil Leaks and other issues

Once an engine or a seal has started to leak, in my experience, simply fixing the problem that caused that leak is not usually enough to fix it, the damage is done and needs repairing.

You now need to address the oil seal or whatever it is that started leaking, and sometimes you can get away with it, which is good news.

Once the leak has been fixed, the problem should no longer be present. But you should prepare yourself for issues that may arise.

For example, having too much oil in the engine may cause harm to the engine since the oil finds its way into all kinds of places in the engine.

Burning Oil

If the engine is burning oil, as we previously discussed, this can cause damage to the catalytic converter.

If you have a diesel engine, it has the potential to clog up your particulate filters because diesel engines produce much larger particles, which means that the filters will eventually become clogged or they will start to burn because the temperature may get too high in those items and they may well burn out, which means that you are causing damage to all of those pollution controls as well.

In a gasoline engine, the spark plugs are quite prone to fouling, and especially if oil is getting into areas where it shouldn't.

If you have put too much oil into your engine, how do you get it out? There are many ways to accomplish this, and the way you choose to do it will usually depend on who you are and how experienced a do-it-yourselfer you are.

How to remove excess engine oil.

Let's say you aren't a capable DIY'er as the problem has happened since we overfilled the oil level in the vehicle.

In this case, going to a garage and obtaining an oil change should be enough to fix the issue in most cases.

Because you have an experienced mechanic on hand, the oil can be drained out, and then it can be refilled to the appropriate level.

When you put oil into your engine, it's incredibly useful to know how much capacity your engine has.

For now, when you add oil to your engine, for the majority of vehicles I've had, the required amount of oil is around four and a half litres.

In this country (the UK), oil is typically sold in containers of five litres.

Therefore, the first thing I would do is get a container of five litres of oil, and then I would drain off half a litre of oil, leaving me with four and a half litres, or whatever the capacity of your sump is.

After that, I would pour that into the engine, and then I would let it settle and check it twice. Leave about 10 minutes between level checks.

That will typically mean that you will also have to pay for an oil change.

When you replace the oil, you will most likely also replace the oil filter and the sump plug.

Because of this, you will be paying to have the job done again, which is a bit of a waste of money.

What about draining the oil via the Sump plug?

Can you drain the oil from the sump? It is not actually that simple to drain oil out of an engine.

I always recommend it whenever you undo the sump plug to replace the washer on it, which is not possible if you are just dribbling out a little oil.

You might get away with using the old washer, but it's a good idea to change the washer.

Slacking it off a little, you may get a dribble of oil coming out but it will flow out quite quickly normally.

It's better to under fill it than to overfill it, so if you're not sure, always err on the side of caution.

You have the problem of not actually knowing how much oil was in the engine already and how much you've drained now, and you're just creating this guesswork situation that could go on and on and on indefinitely with you adjusting the levels and trying to get it right, so the sump is probably best left alone.

However, what will generally occur is that as soon as the sump plug is removed, you will get a jet of the oil coming out of the engine into your catch pan, and you will have to replace it despite the fact that you may believe it contains half a litre or 200 millilitres of oil.

Most of that will drain out and go down into the sun because that's the way they've been designed.

So take that off, it's well above the sump and there's not much that's going to drain out of the engine, so you probably won't achieve very much by slacking off the oil filter at all.

Another method of draining oil is to use a very thin air tube and poke it down the dipstick hole into the engine and use a syringe to just syringe off the oil, which allows you to measure exactly how much oil comes off.

If you just have the hose, if you have a high pressure air compressor, you can blow that across the top of the hose and that will create a suction within the hose and it will pull the oil out.

We hope this has been helpful to you; this covers the basics of what to do if your car is overfilled with oil; & we've highlighted the dangers and problems that can occur to your engine as a result of having too much oil in it; and we've encouraged you to keep an eye on your oil level because having too much oil is bad for the engine, but having too little oil is equally bad for the engine's performance; so please stay tuned if you have any questions or comments.

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